Table 2

Characteristics of study population stratified by racial and ethnic groups

White
(n=72 219)
African American
(n=13 279)
Hispanic
(n=3039)
Native American
(n=611)
Other
(n=3781)
Demographics
Age, mean (SD)72.6 (11.5)68.6 (12.8)69.7 (14.1)66.6 (12.4)71.7 (11.4)
Age group
 <65 years16 140 (22.4)4907 (37.0)992 (32.6)250 (40.9)923 (24.4)
 ≥65 years56 079 (77.7)8372 (63.1)3264 (67.4)361 (59.1)2858 (75.6)
Gender
 Male33 673 (46.6)5310 (40.0)1386 (45.6)269 (44.0)1870 (49.5)
 Female38 546 (53.4)7969 (60.0)1653 (54.4)342 (56.0)1911 (50.5)
Socioeconomic factor
 Disability20 204 (28.0)6188 (46.6)1155 (38.0)313 (51.2)823 (21.8)
 Low income subsidy42 543 (58.9)10 377 (78.2)2741 (90.2)506 (82.8)2896 (76.6)
Country residence
 Metropolitan57 807 (80.0)11 717 (88.2)2840 (93.5)298 (48.8)3586 (94.8)
 Non-metropolitan14 312 (19.8)1542 (11.6)188 (6.2)309 (50.9)183 (4.9)
 Unknown100 (0.1)20 (0.2)11 (0.4)4 (0.7)12 (0.3)
Median income
 Q117 480 (24.2)4267 (32.1)996 (32.8)287 (47.0)323 (8.5)
 Q218 744 (26.0)3279 (24.7)472 (15.5)180 (29.5)668 (17.7)
 Q317 481 (24.2)3142 (23.7)985 (32.4)80 (13.1)1375 (36.4)
 Q418 514 (25.6)2591 (19.5)586 (19.3)64 (10.5)1415 (37.4)
Poverty
 <20%58 894 (81.6)8752 (65.9)1891 (62.2)349 (57.1)3251 (86.0)
 ≥20%13 325 (18.5)4527 (34.1)1148 (37.8)262 (42.9)530 (14.0)
Low income subsidy42 543 (58.9)10 377 (78.2)2741 (90.2)506 (82.8)2896 (76.6)
Medical history
 ESRD1191 (1.7)843 (6.4)177 (5.8)61 (10)176 (4.7)
 PAD38 105 (52.8)7943 (59.8)1658 (54.6)352 (57.6)1716 (45.4)
 Insulin10 328 (14.3)2835 (21.4)738 (24.3)157 (25.7)614 (16.2)
 Elixhauser comorbidity index, mean (SD) (range 0–29)3.8 (2.8)4.4 (3.2)3.9 (2.8)4.0 (3.0)3.5 (2.7)
 DCSI, mean (SD) (range 0–13)2.1 (1.3)2.4 (1.4)2.3 (1.4)2.2 (1.5)2.1 (1.3)
Index diagnosis
 DFU13 726 (19.0)1963 (14.8)319 (10.5)119 (19.5)496 (13.1)
 DFI58 493 (81.0)11 316 (85.2)2720 (89.5)492 (80.5)3285 (86.9)
Specialty for DFU/DFI diagnosis
 Primary care8367 (11.6)1406 (10.6)389 (12.8)95 (15.6)549 (14.5)
 Podiatry16 405 (22.7)2748 (20.7)628 (20.7)69 (11.3)775 (20.5)
 Specialist47 447 (65.7)9125 (68.7)2022 (66.5)447 (73.2)2457 (65)
Place of DFU/DFI diagnosis
 Hospital4098 (5.7)1041 (7.8)174 (5.7)57 (9.3)172 (4.6)
 Outpatient10 632 (14.7)1797 (13.5)328 (10.8)253 (41.4)370 (9.8)
 ED809 (1.1)213 (1.6)44 (1.5)17 (2.8)42 (1.1)
 Home health agency476 (0.7)85 (0.6)26 (0.9)1 (0.2)18 (0.5)
 Skilled nursing facility1628 (2.3)363 (2.7)51 (1.7)8 (1.3)82 (2.2)
 Other54 576 (75.6)9780 (73.7)2416 (79.5)275 (45.0)3097 (81.9)
Early PCP follow-up (30 days after diagnosis)35 242 (48.8)6742 (50.8)1523 (50.1)328 (53.7)1892 (50.0)
Revascularization within 12 months5499 (7.6)1899 (14.3)345 (11.4)101 (16.5)334 (8.8)
Healthcare utilization after DFU/DFI diagnosis
 ED visits per person, mean (SD)0.02 (0.2)0.03 (0.2)0.03 (0.2)0.03 (0.2)0.01 (0.1)
 Outpatient visits per person, mean (SD)1.592.252.392.231
 Inpatient hospital stay per person, mean (SD)13.93 (27.6)19.26 (28.7)15.4 (21.6)15.65 (26.95)15.65 (27.0)
 Number of major amputations1068 (1.5)507 (3.8)64 (2.1)31 (5.1)56 (1.5)
 Unadjusted risks of major amputationReferenceHR=2.65, 95% CI=2.38 to 2.94, p<0.0001HR=1.41, 95% CI=1.10 to 1.82, p=0.0007HR=3.62, 95% CI=2.53 to 5.17, p<0.0001HR-1.00, 95% CI=0.77 to 1.31, p=0.98
  • Values are reported as number (%) unless otherwise specified.

  • DCSI, Diabetes Complications Severity Index; DFI, diabetic foot infection; DFU, diabetic foot ulcer; ED, emergency room; ESRD, end-stage renal disease; PAD, peripheral artery disease; PCP, primary care physician; Q, quartile.